Industrial high-temperature reformer and reforming method

ABSTRACT

An industrial high temperature reformer and the reforming method in which a temperature of the reforming furnace is maintained at 1000° C. or higher by burning the coke, and a temperature of at least an upper half of the reforming furnace is maintained at 1200° C. or higher by burning the syngas, thereby producing syngas at a capacity of 500 m 3 /hour or more by reforming all carbonaceous feedstock which is supplied to the reforming furnace.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/568,989, filed Oct. 24, 2017, which is a national phase ofInternational Application No. PCT/KR2016/012639, filed Nov. 4, 2016,which claims priority to Korean Patent Application No. 10-2015-0159511,filed Nov. 13, 2015, the entire contents of which are incorporatedherein by reference.

FIELD

The present invention relates to an industrial high temperature reformer(aka Kim reformer-XT) which is obtained by improving a high temperaturereformer (Korean Patent No. 0637340) patented to the present applicant,i.e., a small-sized experimental reformer (aka Kim reformer). In theprocess, its production capacity of syngas has improved from 100 m³/hourto 500 m³/hour or more, and also relates to its reforming method.

BACKGROUND

The high temperature reformer technology began when the German chemistLurgi suggested a coal-gas reaction(C+H₂O→CO+H₂). Before the presentapplicant disclosed the patented high temperature reformer (patentdocuments 1 through 7), the coal-gas reaction was limited to coalgasification; ground coal is combusted with oxygen gas in order to bringup the reactor temperature, and then hot steam is injected into the coalfurnace. This method of coal gasification is known as the partialoxidation method, and the resulting reaction temperature runs justaround 1,000° C., and a mixture of hydrocarbons are generated. Howeversyngas (CO+H₂) after extensive gas separation amounts to about 5% oftotal gas mixture produced. Furthermore, the temperature of thereforming furnace could not be maintained at 1200° C. or higher byburning coal. Currently, it is known that only the SASOL company ofSouth Africa maintains an economical syngas production.

At the end of the last century, the present applicant reexamined theLurgi coal-gas reaction. The results of the experiment (see non-patentdocument 1) were significantly different from the facts which werewidely known at the time. The results of the experiment were as in thefollowing. 1) The temperature at which all carbon reformed withoutcatalyst to carbon monoxide gas and all hydrogen atom reduced into H₂gas was just above 1200° C.; 2) Not only carbon of coal, but of allcarbonaceous substance reformed into carbon monoxide (CO) at 1200° C. orhigher; 3) At the temperature above 1200° C., all hydrocarbons includingmethane disappeared quickly, and all other hydrocarbons were notdetected by a gas detector. The only detected carbon species were CO andCO₂. Since the gas generated at a temperature of 1200° C. or higher didnot contain any carbon species except for CO gas, unlike in aconventional gasification method, it was not necessary to carry out thegas separation process. The present applicant conducted additionalexperiments with great interest in the results of 2). The experimentswere conducted on a waste tire, crude rubber, synthetic resin andbiomass, and only biomass had a problem. The reason for this is thatbiomass contains a large amount of moisture, and thus the region nearthe carbons of biomass could not be heated to a temperature of 1200° C.within a short period of time. In particular, the carbon reformingreaction was an endothermic reaction, and a heat of 1200° C. requiredfor the reforming reaction was not supplied to the carbons.

When the present applicant became aware that the Lurgi coal-gas reactionreached the thermal equilibrium at 1200° C., the present applicantconstructed a reforming furnace capable of maintaining a temperature of1200° C., i.e., the most efficient condition for the reaction. Thereforming furnace was named Kim reformer (see patent document 1), andwas constructed for experimental purposes.

However, the Kim reformer merely produces syngas at a capacity of 100m³/hour, and has a problem in that 30% of generated syngas has to beburnt and used as heat source for the purpose of the continuousoperation thereof. In other words, for the Kim reformer to be widelyused for industrial purposes, the reformer can be said to be economiconly when the reformer can produce syngas at a capacity of 500 m³/houror more.

SUMMARY

The object of the present invention is to provide an industrial hightemperature reformer and the reforming method which can produce syngasat a capacity of 500 m³/hour or more. In the industrial high temperaturereformer and the reforming method, a temperature of the reformingfurnace is maintained at 1000° C. or higher by burning the coke, and atemperature of at least an upper half of the reforming furnace ismaintained at 1200° C. or higher by burning the syngas, therebyreforming all carbonaceous feedstock which is supplied to the reformingfurnace.

In order to accomplish the above object, the present invention providesan industrial high temperature reformer comprising: a reforming furnacereforming carbonaceous feedstock; a carbonaceous feedstock inletsupplying carbonaceous feedstock to the reforming furnace; a coke supplyunit supplying coke to the reforming furnace; a first oxygen inletsupplying oxygen to the reforming furnace; a steam inlet supplying steamto the reforming furnace; a syngas outlet formed in an upper section ofthe reforming furnace; and a syngas inlet supplying syngas to thereforming furnace; wherein a temperature of the reforming furnace ismaintained at 1000° C. or higher by burning the coke with the oxygen,and a temperature of at least an upper half of the reforming furnace ismaintained at 1200° C. or higher by burning the syngas supplied via thesyngas inlet.

In this case, the first oxygen inlet can be formed in the lower sectionof the reforming furnace, and a second oxygen inlet can be formed in themid-section of the reforming furnace. The two carbonaceous feedstockinlets can be formed in the mid-section of the reforming furnace, andthe second oxygen inlet can be formed in between the two carbonaceousfeedstock inlets.

The oxygen supplied to the reforming furnace can be fully used up toburn the coke and the syngas supplied via the syngas inlet. The syngassupplied via the syngas inlet can be part of syngas discharged via thesyngas outlet, and the high temperature syngas discharged via the syngasoutlet can pyrolyze the carbonaceous feedstock and be then cooled.

Furthermore, the present invention provides the industrial hightemperature reforming method comprising: a first step of supplying coketo a reforming furnace; a second step of supplying oxygen to thereforming furnace, and maintain a temperature of the reforming furnaceat 1000° C. or higher by burning the coke; a third step of supplyingsteam to the reforming furnace; a fourth step of maintaining atemperature of at least an upper half of the reforming furnace at 1200°C. or higher by burning a gas mixture (CO₂, H₂0, CO, and H₂) generatedthrough the burning of the coke and the steam and/or syngas supplied tothe reforming furnace; and a fifth step of supplying carbonaceousfeedstock to the reforming furnace, and generating syngas by reformingthe carbonaceous feedstock.

In this case, the oxygen used to burn the coke at the second step may besupplied via a lower section of the reforming furnace, and the oxygenused to burn the gas mixture and/or syngas at the fourth step may besupplied via a mid-section of the reforming furnace. The syngas at thefourth step may be part of the syngas generated at the fifth step, andthe high temperature syngas generated at the fifth step may pyrolyze thecarbonaceous feedstock and be then cooled.

In an industrial high temperature reformer (Kim reformer-XT) accordingto the present invention, the overall reforming furnace is maintained at1000° C. or higher by using an abundant coke pile as the main heatsource, and at least the upper half of the reforming furnace ismaintained at 1200° C. or higher by using syngas as an auxiliary heatsource, thereby providing the effect of rapidly reforming carbonaceousfeedstock in a gaseous state and generating syngas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing an industrial high temperature reformeraccording to the present invention.

FIG. 2 is a right side view showing the industrial high temperaturereformer according to the present invention.

FIG. 3 is a longitudinal sectional view showing the industrial hightemperature reformer according to the present invention.

DETAILED DESCRIPTION

FIG. 1 shows a front of an industrial high temperature reformeraccording to the present invention, FIG. 2 shows a right side of theindustrial high temperature reformer according to the present invention,FIG. 3 shows a longitudinal section of the industrial high temperaturereformer according to the present invention.

The present invention provides an industrial high temperature reformercomprising: a reforming furnace 10 reforming carbonaceous feedstock; acarbonaceous feedstock inlet 20 supplying carbonaceous feedstock to thereforming furnace 10; a coke supply unit 30 supplying coke to thereforming furnace 10; a first oxygen inlet 40 supplying oxygen to thereforming furnace 10; a steam inlet 50 supplying steam to the reformingfurnace 10; a syngas outlet 60 formed in an upper section of thereforming furnace 10; and a syngas inlet 70 supplying syngas to thereforming furnace 10; wherein a temperature of the reforming furnace 10is maintained at 1000° C. or higher by burning the coke with the oxygen,and a temperature of at least an upper half of the reforming furnace 10is maintained at 1200° C. or higher by burning the syngas supplied viathe syngas inlet 70.

An industrial high temperature reformer (Kim reformer-XT) according tothe present invention is a significantly efficient reformer whichgenerates syngas by reforming carbons, constituting all the carbonaceousfeedstock, into carbon monoxide CO without a catalyst and then reducinghydrogen into hydrogen gas. The temperature of the reforming furnace 10may be maintained at 1000° C. or higher by heat generated in the cokepile, and the temperature of at least the upper half of the reformingfurnace may be continuously maintained at 1200° C. or higher bycirculating a portion of the syngas generated at 1200° C. or higher andburning it. It burns just enough syngas required for maintaining thetemperature of the at least the upper half of the reforming furnace 10at 1200° C. or higher, rather than the whole reforming furnace 10. Thismechanism may be viewed as a significantly energy efficient invention.

The reforming furnace 10 has the height of 3 m and the outer diameter of1 m. The carbonaceous feedstock inlets 20 are formed about themid-section of the reforming furnace 10, one above the mid-section andthe other below it. When the temperature of the upper half of thereforming furnace 10 reaches to 1200° C. or higher, gaseous carbonaceoussubstance and well ground (μm size) powder form of carbon react quicklyto generate syngas. However when the feedstock is liquid or solid, ittakes time for carbon atoms of liquid or solid feedstock to come to athermal equilibrium with surrounding temperature of 1200° C. Although inthe case of coal, the time may be reduced by finely grinding coal tomicrometer size, significant energy consumption may occur during thisprocess. Accordingly, if coal is pyrolyzed and reduced into flue gas,and oil, and then injected into the reformer, a rapid reforming mayfollow and syngas is generated. Waste plastics may also be pyrolyzed asin the case of coal, or a pyrolyzer may be directly connected to thecarbonaceous feedstock inlet 20 and carbonaceous feedstock (flue gas,and oil) obtained through pyrolysis may be supplied.

In particular, biomass has a large amount of moisture, and thus tar isleft even when biomass is dried. However, tar is the main source ofcarbons, and thus a large amount of syngas can be obtained bycontinuously reforming tar.

In the case of food waste, hydrocarbon may be separated from water via ahydrogenation process (see Korean Patent 1146582 issued to the presentapplicant). Since the temperature of the syngas outlet 60 is equal to orhigher than 1200° C., the high temperature syngas generated in thereformer may be used as a heat source required for the high temperaturehydrolysis of food waste to recover the hydrocarbons from the foodwaste.

When a large number of carbon sources are obtained by performingappropriate preprocessing of waste, biomass, etc. and then reforming isperformed, a large amount of syngas can be produced, and hydrogen gas,other renewable energy resources and various chemical materials can beproduced.

A coke supply unit 30 configured to supply coke is formed in the lowerpart of the mid-section of the reforming furnace 10, and the coke supplyunit 30 may include a supply pipe 31 configured such that a transferscrew is formed therein and a hopper 32 formed above the supply pipe 31and may be modified into various forms, such as a hydraulic cylinder, ablower, and the like. Petroleum coke or coal coke generated during coalgasification may be used. In Korea, oil refinery companies treatpetroleum coke as waste, and thus using petroleum coke as the main heatsource is recommended as being renewables.

A first oxygen inlet 40 configured to supply oxygen is formed in thelower section of the reforming furnace 10. The coke supplied by the cokesupply unit 30 is stacked in the lower section of the reforming furnace10, and the first oxygen inlet 40 supplies oxygen to a pile formed bythe stacked coke. Furthermore, a steam inlet 50 configured to supplysteam is formed above the first oxygen inlet 40, a syngas inlet 70configured to supply syngas is formed in the mid-section of thereforming furnace 10, a second oxygen inlet 42 may be formed between thetwo carbonaceous feedstock inlets 20, and an ash remover 35 is formed atthe lower end of the reforming furnace 10.

The coke pile supplied via the coke supply unit 30 and located in thelower section of the reforming furnace 10 is burnt along with the oxygensupplied via the first oxygen inlet 40, and provides high temperatureheat equal to or higher than 1500° C. A gas mixture (CO₂, H₂O, CO, andH₂; generated from the burning of the coke and the use of the steamsupplied via the steam inlet) generated in the coke pile rises up to theupper section of the reforming furnace 10, and maintains the temperatureof the entire reforming furnace 10 at 1000° C. or higher. The gasmixture and/or syngas (supplied via the syngas inlet 70) may be burnt,and maintain the temperature of at least the upper half of the reformingfurnace 10 at 1200° C. or higher. When the temperature of the upper halfof the reforming furnace 10 is maintained at 1200° C. or higher, thecarbonaceous feedstock entering via the carbonaceous feedstock inlets 20is reformed and generates syngas, and the generated syngas is dischargedvia the syngas outlet 60 formed in the upper section of the reformingfurnace 10 and is then stored. In this case, a portion of the syngasdischarged from the syngas outlet 60 may be redirected to the reformingfurnace 10 via the syngas inlet 70, is burnt therein, and continuouslymaintains the temperature of at least the upper half of the reformingfurnace 10 at 1200° C. or higher.

In other words, the overall reforming furnace 10 is maintained at 1000°C. or higher by the burning of the coke, and the temperature of at leastthe upper half of the reforming furnace 10 is increased to 1200° C. orhigher by burning a small amount of syngas (CO+H₂) generated in the cokepile and/or the syngas supplied via the syngas inlet 70. Thereafter,reforming is sustained by injecting carbonaceous feedstock. A sufficientamount of the generated syngas is transferred to the upper half of thereforming furnace thru circulating a portion of the generated syngas.The generated syngas is to supplement the syngas rising from the cokepile, thereby providing the heat source required for the endothermicreforming reaction. When the upper half of the reforming furnacemaintains the thermal equilibrium at the 1200° C. or higher, thereforming reaction takes place very rapidly.

In this case, in order to activate the burning of the gas mixture(generated through the burning of the coke and the use of the steamsupplied via the steam inlet) and/or the syngas (supplied via the syngasinlet 70), a second oxygen inlet 42 may be formed at the mid-section ofthe reforming furnace 10, and the upper half of the reforming furnace 10may be effectively maintained at 1200° C. The oxygen inside thereforming furnace 10 is completely used up to burn the coke, the gasmixture (generated through the burning of the coke and the use of thesteam supplied via the steam inlet), and the syngas (supplied via thesyngas inlet), and thus no oxygen is detected in the syngas outlet 60.There should be no oxygen left within the reforming furnace 10 at alltime, strictly oxygen deficient mode.

It is preferred that the oxygen supplied via the first oxygen inlet 40is completely used up to burn the coke and that the oxygen supplied viathe second oxygen inlet 42 is used to burn the gas mixture (generatedthrough the burning of the coke and the use of the steam supplied viathe steam inlet) and/or the syngas (supplied via the syngas inlet).

The high temperature syngas discharged via the syngas outlet 60 iscooled via a pyrolyzing furnace in which biomass, coal, or the like,i.e., solid or liquid carbonaceous feedstock, is pretreated, and thesyngas having the remaining heat is cooled to room temperature andstored in a storage tank.

The present invention provides the industrial high temperature reformingmethod comprising: the first step of supplying coke to a reformingfurnace; the second step of supplying oxygen to the reforming furnace,and maintain a temperature of the reforming furnace at 1000° C. orhigher by burning the coke; the third step of supplying steam to thereforming furnace; the fourth step of maintaining a temperature of atleast an upper half of the reforming furnace at 1200° C. or higher byburning a gas mixture (CO₂, H₂0, CO, and H₂) generated through theburning of the coke and the steam and/or syngas supplied to thereforming furnace; and the fifth step of supplying carbonaceousfeedstock to the reforming furnace, and generating syngas by reformingthe carbonaceous feedstock.

The first step is the step of supplying coke to the reforming furnace 10via the coke supply unit 30. The supplied coke is congregated in thelower section of the reforming furnace 10, and forms a coke pile.

The second step is the step of supplying oxygen to the reforming furnace10, and maintaining the temperature of the reforming furnace 10 at 1000°C. or higher by burning the coke. At the third step, steam is suppliedto the reforming furnace 10 via the steam inlet 50.

The fourth step is the step of maintaining the temperature of at leastthe upper half of the reforming furnace 10 at 1200° C. or higher. Thetemperature of at least the upper half of the reforming furnace 10 isincreased to 1200° C. or higher by burning a gas mixture (CO₂, H₂0, CO,and H₂) generated through the burning of the coke and the use of thesteam and/or the syngas supplied to the reforming furnace 10 via thesyngas inlet 70.

When the temperature of the at least the upper half of the reformingfurnace 10 is maintained at 1200° C. or higher, carbonaceous feedstockis supplied to the reforming furnace 10 via the carbonaceous feedstockinlets 20, syngas is generated by reforming the carbonaceous feedstock,and the generated syngas is discharged via the syngas outlet 60.

In this case, the oxygen used to burn the coke at the second step can besupplied via the first oxygen inlet 40 which is formed in a lowersection of the reforming furnace 10, and the oxygen used to burn the gasmixture or syngas at the fourth step can be supplied via the secondoxygen inlet 42 which is formed at the mid-section of the reformingfurnace 10. The syngas at the fourth step can be part of the syngasgenerated at the fifth step, and the high temperature syngas generatedat the fifth step can pyrolyze the carbonaceous feedstock and be thencooled.

A main heat source is the coke pile located in the lower section of thereforming furnace 10. A high temperature of 1500 to 1800° C. isgenerated by burning the coke along with the oxygen. When steam isgradually supplied over the coke pile located in the lower section ofthe reforming furnace 10 via the steam inlet 50, a gas mixture (CO₂,H₂0, CO, and H₂) rises up and heats the overall reforming furnace 10 to1000° C. or higher. When hydrogen gas H₂ is continuously detected at thesyngas outlet 60, oxygen gas O₂ is gradually injected in small amountsvia the second oxygen inlet 42. When the amount of syngas generated inthe coke pile is increased by increasing the supply of the steam via thesteam inlet 50 and the temperature of the upper half of the reformingfurnace 10 reaches 1200° C. or higher by carefully increasing the oxygeninjected via the second oxygen inlet 42, carbonaceous feedstock isintroduced via the carbonaceous feedstock inlets 20. A part of thesyngas (<10%) discharged via the syngas outlet 60 is supplied to thereforming furnace 10 via the syngas inlet 70. The purpose of thesupplied syngas is to exhaust the oxygen gas entering via the firstoxygen inlet 40 and/or second oxygen inlet 42 and to maintain thetemperature of the upper half of the reforming furnace 10 at 1200° C. orhigher. A region above 1200° C. is a region in which the heat balanceand the reforming reaction to start are established, and therefore thereforming reaction takes place most efficiently without the presence ofa catalyst. The syngas production capacity of the industrial hightemperature reformer (Kim reformer-XT) according to the presentinvention is 500 m³ or more. When the temperature of the upper half ofthe reforming furnace 10 is decreased to 1200° C. or lower, the supplyof the carbonaceous feedstock may be stopped and the process may bere-started, or the amounts of syngas supplied to the syngas inlet 70 maybe increased, and then the oxygen supply.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that the scope and spirit of the present invention are notlimited to these embodiments, and various modifications, additions andsubstitutions are possible, without departing from the scope and spiritof the invention as disclosed in the accompanying claims.

The present invention can produce syngas at a capacity having improvedfrom 100 m³/hour to 500 m³/hour or more by improving a small-sizedexperimental reformer into an industrial reformer.

1. An industrial high temperature reforming method comprising: a firststep of supplying coke to the reforming furnace; a second step ofsupplying a first oxygen to the reforming furnace, and maintaining atemperature of the reforming furnace at 1000° C. or higher by burningthe coke with the first oxygen; a third step of supplying steam to thereforming furnace; a fourth step of maintaining a temperature of atleast an upper half of the reforming furnace at 1200° C. or higher byburning at least one of a gas mixture and a first syngas, with a secondoxygen; and a fifth step of supplying carbonaceous feedstock to thereforming furnace, and generating a second syngas by reforming thecarbonaceous feedstock, wherein the gas mixture is generated through theburning of the coke and the steam, and the first syngas is supplied tothe reforming furnace.
 2. The industrial high temperature reformingmethod of claim 1, wherein the oxygen used to burn the coke at thesecond step is supplied via a lower section of the reforming furnace,and the oxygen used to burn at least one of the gas mixture and thefirst syngas at the fourth step is supplied via a mid-section of thereforming furnace.
 3. The industrial high temperature reforming methodof claim 1, wherein the first syngas at the fourth step is part of thesecond syngas generated at the fifth step, and the high temperaturesyngas generated at the fifth step pyrolyzes the carbonaceous feedstockand is then cooled.
 4. The industrial high temperature reforming methodof claim 1, wherein two carbonaceous feedstock inlets are formed in amid-section of the reforming furnace, and a second oxygen inlet isformed between the two carbonaceous feedstock inlets.